From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1751747AbbEGR3U (ORCPT <rfc822;w@1wt.eu>);
	Thu, 7 May 2015 13:29:20 -0400
Received: from casper.infradead.org ([85.118.1.10]:60495 "EHLO
	casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751365AbbEGR3T (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 7 May 2015 13:29:19 -0400
Date: Thu, 7 May 2015 19:29:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        NeilBrown <neilb@suse.de>
Subject: Re: pmu_dev_alloc; warning at at kernel/locking/lockdep.c:3002
 lockdep_init_map
Message-ID: <20150507172905.GE16478@twins.programming.kicks-ass.net>
References: <554B6E78.2090608@linux.intel.com>
 <20150507140557.GV21418@twins.programming.kicks-ass.net>
 <20150507162523.GB12245@htj.duckdns.org>
 <554B9305.301@linux.intel.com>
 <20150507170626.GA27504@twins.programming.kicks-ass.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20150507170626.GA27504@twins.programming.kicks-ass.net>
User-Agent: Mutt/1.5.21 (2012-12-30)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, May 07, 2015 at 07:06:26PM +0200, Peter Zijlstra wrote:
> On Thu, May 07, 2015 at 05:29:57PM +0100, Tvrtko Ursulin wrote:
> > >>> May  7 11:58:20 skl kernel: [    6.066696] futex hash table entries: 1024 (order: 5, 131072 bytes)
> 
> > >>> May  7 11:58:20 skl kernel: [    6.329549] HugeTLB registered 2 MB page size, pre-allocated 0 pages
> 
> 
> > > sysfs by default uses lockdep key embedded in attrs.  It looks like
> > > somebody is making on-heap copies of attrs and using them as the group
> > > attrs.  What's the offending pmu type?
> > 
> > I am not familiar with this area, is this the answer?
> 
> Nope, that's way before you get the fail. initcall_debug might get you
> the right answer, but I suspect its the intel_uncore driver.
> 
> I see arch/x86/kernel/cpu/perf_event_intel_uncore.c:uncore_type_init()
> do exactly what TJ says, its dynamically allocating struct attribute.
> 
> Now, let me try and trigger that locally, that should not be skylake
> specific at all.

4.1-rc2+ with lockdep enabled boots without issue on my ivb-ep, no idea
what's going on on your skylake thingy.